Sheet rolling mill



April 3, 1934;" A. PATERSON. 90

51mm ROLLING MILL Filed Dec. 21, 1931 INVENTOR 1 BY/OWMIO W A TTORNEYS 1,, z; 1/? 4 T1 N9- v B /w' Patented Apr. 3,' 1934 UNITED STATES PATENT} OFFICE SHEET ROLLING MILL Alexander PatcrsomBuflala N. Y. Application December 21, 1931, Serial N0. 582,208

'7- Claims.

are effected upon a perfectly rectangular sheet of metal, each reduction being uniform throughout the cross-section of the metal so as to preserve the rectangular form.' Owing to several factors which may vary the contour of the rolls as, for

' example, roll expansion and deflection this ideal condition cannot practically be obtained. The variable factors, however,-may be controlled so as to provide a roll contour which is eitherconcave or convex. The former has been more generally adopted, the rolls being ground concave to such an extent as to compensate for subsequent expansion under working conditions. Owing,

creases correspondingly.

nitude of the reductions is progressively decreased, the magnitude of the deflections detherefore, approaches a flat or rectangular form as its thickness is reduced.

In the rolling of sheet metal by a single stand mill, a sheet or pack which has been heated is passed ,and repassed between the same pair of rolls to effect successive reductions. The screws of the stand are set between reductions to regulate or control the magnitude of the reductions, the sheet or pack approaching a flat or rectangular cross-section as the deflection of the rolls decreases in accordancewith the magnitude of the reduction. In the-ordinary mill, the sheet or pack is given four or flve passes for one heating and in the first pass approximately one-half of the total reduction is effected, the succeeding passes being relatively less eflicient because of the rapid cooling of the metal. In order to avoid such heat losses to some extent. another method has been proposed which for convenience will be The sheet or pack,'

employed in connection with the working rolls, the former co-operating with the latter to maintain the deflection of the working rolls at a mini- .mum in order to adhere as close as possible to the ideal operating condition. The working rolls" with the co-operation of the backing-up rolls form the sheets or packs with a substantially uniformcross-section in each'pass. If a change to a difierent cross-section in any such pass, i. e. with respect to a particular screw or other fac tor adjustment, be required it is necessary according to the practice heretofore prevailing to replace the backing-up rolls or. the working rolls with other backing-up rolls or working rolls, as the case may be, suitable for the purpose in view.

The principal object of the present invention is a mill wherein the pass, with respect to a particular screw adjustment," may be varied at will without the necessity-of the replacement of any of the parts of the mill, this object contemplating anovel form of backing-up roll which co-opcrates with a working roll in such a manner that the degree of deflection of the latter may readily be controlled. A further object is a novel method of controlling the working pass of the mill.

The invention is illustrated in the accompanyingdrawing, in which:--

Figure 1 is a front elevation of a two-high mill in which features of the invention are incorporated. I

Figure 2 is a vertical section taken along line 22 of Figure l.

Figure 3 is a front elevation of a mill of modifled form illustrating an embodiment of the invention.

a mill of further modified form illustrating another embodiment of the invention.

The mill, as illustrated for example in Figure 1, includes upper and lower working rolls 5 and 6 respectively and co-operating companion upper and lower'backing-up rolls 7 and 8. The said rolls are mounted in suitable housings 9, each of which isprovided with a conventional adjusting screw 10 by means of which the magnitude of the reductions is'controlled.

The backing-up rolls are formed or provided with end collars-11 and preferably with intermediate collars 12, the latter preferably being of a suitably smaller diameter than the former. The collars are adapted to co-operate with the working rolls to limit the deflection of the latter during passage of a sheet or pack between them so that the sheet or pack will be formed with a predetermined cross-sectional convexity.

9o Figure 4 is a fragmentary view in elevation of The pressure exercised by the backing-up rolls upon the working rolls, and hence the degree of deflection of the working rolls, depends, among other factors, upon the relative diameters of the planes of the backing-up rolls at the points of contact with the working rolls, and this factor remains constant as the temperature remains constant. In accordance with the invention, the diameters of the collars are predetermined as may be necessary in the particular case whereby the deflection of the working rolls will be limited to a value adequate for the production of sheets or packs of the desired cross-section. It will be understood that by relatively increasing or decreasing the diameters of the intermediate sections of the backing-up rolls, i. e. in the preferred construction the diameters of the intermediate collars whereby they will be of diameters relatively greater or relatively less than the diameters of the end collars, the deflection of the working rolls will be controlled with reference to the crosssection of the sheet or pack. In other words, an increase in the diameters of the intermediate collars 12 relatively to the end collars will result in a corresponding reduction in the deflection of the working rolls while any'relative decrease in the diameters of the intermediate collars will result in a corresponding increase in the deflection of the working rolls.

In controlling the deflection of the working rolls the end collars 11 may be availed of if desired, this depending in most cases upon the degree of deflection which is to be obtained. The collars 11 may be relatively expanded while the collars 12 are contracted, thereby providing for the maximum degree of deflection of the working rolls. On the other hand, the collars 11 may be contracted while the collars 12 are relatively expanded so as to maintain the deflection of the working rolls at a minimum, it being understood that the diameter of the collars may be controlled within limits to regulate the deflection of the working rolls in such a manner as to produce sheets or packs of convex, rectangular or concave cross-section. The collars 12 are preferably suitably less in diameter than the collars 11, in order to enable the regulation of the deflection of the working rolls within a wide range. The stresses at the ends of the backing-up rolls are divided between the blocks in which the necks of the rolls are journalled and the collars 11 while the stresses at the centers of the working rolls are taken up solely by the collars 12. The latter, therefore, are preferably designed to provide larger areas for contact with the working rolls than the end collars. The variations in the relative diameters of the collars will for most purposes be of the order of a few thousandths of an inch, that is to say from approximately two thousandths of an inch to twelve thousandths according to circumstances, and such or other variations as circumstances may require, may, therefore be readily "obtained by abrasive or cutting operations or by the use of suitable heating and cooling devices. I

For varying the diameters of the collars by means of abrasive or cutting operations it is not necessary to remove any part of the mill since suitable abrasive blocks or cutting tools may be applied to the collars while the backing-up .roll is rotated in its supports until the desired adjustment has been made. -Where heating and cooling means may be employed these may be of the forms well known in the art. Regulation of the diameter of the collars by the abrasive or cutting methods is, however, preferred.

The collars may be varied in number as circumstances may require. Thus, it is within the contemplation of the'invention to omit the intermediate collars and utilize the intermediate portion of the body of the backing-up roll for exercising pressure upon the working roll, varying or relatively varying the diameter of such intermediate portion in the manner described. In the modification shown in Figure 3 the backingup rolls 7 and 8 are formed or provided with two intermediate collars 13, the latter and the end collars 11 providing four contact areas which co-operate with the workingrolls 5 and 6 to limit the deflection of the latter to a predetermined degree.

In the modification shown in Figure 4 the backing-up roll 7 is corrugated or fluted as at-14 between the end and intermediate collars. This construction has particular reference to the adjustment of the diameters of the collars by the use of heating andcooling means and enables facility of control of the expansion and contraction of the collars by preventing the transmission of the heat which is applied to one or more of the collars to adjacent collars, the fluted body portions of the rolls serving to dissipate the heat before it is transmitted-to the adjacent collars.

In the operation of the various forms of mills illustrated, it will be apparent that the pass provided by the workingrolls may be regulated by the screws 10 to determine the magnitude of the reduction of the sheets or packs while the collars may be controlled in diameter to limit the deflection of the working rolls, whereby the sheets or packs are formed with a predetermined crosssection. If, for'any reason, it be-desired to vary the cross-section of the sheets or packs, the collars may be regulated in diameter to enable the desired change. It will also beapparent that the initial diameters of the collars maybe such as to enable the production of sheets or packs,

with aopredetermined cross-section without the use of heating or cooling devices, the collars funcationing in such a case similarly to conventional backing-up rolls.

In the various embodiments illustrated each of i the working rolls has a backing-up roll associated with it. It is to be understood, however, that this is by way of illustration only, since the advantages of the invention may beobtained by the use of such a backing-up roll in connection with only one of the working rolls, that is to say in a three-high mill. The diameter of the collars need be only slightly greater than the diameter of the body portions of the rolls, this relation being exaggerated in the drawing for the sake of clearness.

I claim as my invention: 1. In a sheet rolling mill, the combination with a working roll, of a backing-up roll formed with a body portion spaced from the working roll, a

collar carried by said backing-up roll and providing an area for local contact with said working roll and a second collar of relatively smaller diameter carried by said backing-up roll and providing a second area for local contact with said working roll, whereby the backing-up roll is 7 collar carried by said backing-up roll andpro-- viding an area for local contact with said working roll and a second collar of relatively smaller diameter carried by said backing-up roll and providing a second area for local contact with said working roll, whereby the backing-up roll is adapted through the agency of said collars to limit the degree ofydeflection of said working roll, said collar of smaller diameter being adapted for diametrical variation in accordance with its temperature, whereby the pass delimited by the working roll may be controlled by varying the temperature of said collar of smaller diameter.

3. In a sheet rolling mill, the combination with a working roll, of a backing-up roll formed with a body portion spaced from the working roll, a plurality of collars carried by the backing-up roll and providing a plurality of areas for local con- .tact with said working roll, one of said collars being of a relatively smaller diameter than the others, the backing-up roll being adapted through the agency of said collars to limit the degree of deflection of said working roll, thev collar of a relatively smaller diameter being adapted for diametrical variation in accordance with its temperature, whereby the pass delimited by the'working roll may be controlled by varying the temperature of said collar. v

4. In a sheet rolling mill, the combination with a working roll, of a backing-up roll formed with a body-portion spaced from the working roll, a

thereof and providing areas for local contact with collar carried by said backing-up roll at each end the working roll, a third collar of relatively smaller diametercarried by said backing-up roll between said, collars first. mentioned and also providing an area for local contact with said working roll, whereby the backing-up roll is adapted through the agency of said collars to limit the deflection of said working roll to a predetermined degree.

5. In a sheet rolling mill, the combination with a working, roll, of a backing-up roll formed with a body portion spaced from the workingn'oll, a collar carried by said backing-up roll at each end thereof and providing areas for local contact with said working roll, a third collar 01! relatively smaller diameter carried by said backing-up roll between said collars first mentioned and also provlding an area for local contact with said working roll, whereby the backing-uproll is adapted through the agency of said collars to limit the deflection oi the working roll, said collar of smaller diameter being adapted for diametrical variation in accordance with its temperature, whereby the pass delimited by the working roll may be controlled by 'varying the temperature or said smaller collar.

6. In a sheet rolling mill, the combination'with a working roll, of a backing-up'roll formed with a body portion spaced from the working roll and a plurality of collars carried by said backing-up roll and providing a plurality of areas for local contact with said working roll, whereby the backing-up roll is adapted through the agency of said collars to limit the deflection of said working roll, said collars being adapted for diametrical variation in accordance with their temperature, whereby the pass delimited by the working roll may be controlled by varying the temperature of one of said collars, said body portion being fluted between sald-last mentioned collar and an adjacent collar in order to prevent the transmission ,of heat from said last mentioned collar to said ing roll, whereby the backing-up roll is adapted through the agency of said collars to limit the deflection of said working roll, said collarsbeing adapted for diametrical variation in accordance with their tem erature, whereby the pass delimited by the working roll may be controlled by ,varying the temperature of one of said collars,

said body portion being fluted between said last mentioned collar and an adjacent collar in order to prevent the transmission of heat from said last mentioned collar to said adjacent collar.

ALEXANDER PATERSON. 

